1. Field of the Invention
The present invention relates to safety razor blades and coatings for the cutting edges of such blades. More particularly, the present invention relates to cutting edge adherent fluorocarbon polymer coatings having improved shaving characteristics.
2. Description of the Prior Art
In addition to the usual problems involved in maintaining a sharp edge on razor blades during extended storage periods and through repeated use, razor blades used for shaving hair involve the problems of blade pull on the hairs, the effect of the blade action on the skin, as well as the overall ease with which such shaving can be accomplished. Blade comfort can be characterized as a function of lubricity and pull.
In order to lessen some of the undesirable effects which occur during the use of razor blades, various lubricants have been utilized. For example, blades have been coated with oil in order to use them in many applications. In addition, shaving preparations, such as shaving soaps and the like, have been employed to provide improved performance. Furthermore, blade edges have been made sharper for greater cutting ease and blades have been developed of metals which will hold a sharper edge for longer periods of time. Blades have also been made of metals which will resist attach by air and various liquids which cause the degradation of the blade.
Some coatings have been developed to provide blades with a degree of protection against air and liquids which attack them. For example, wax coatings have been applied to steel blades to prevent the blades from rusting due to the action of water. In addition, certain materials have been applied to blades in order to facilitate shaving with them. Such materials have included silicone coatings and halogenated hydrocarbon coatings.
Further, U.S. Pat. No. 3,071,856 discloses the use of polymers of tetrafluoroethylene as a coating for a razor blade cutting edge to reduce blade pull during shaving. U.S. Pat. No. 3,224,094 discloses an adherent blade cutting edge coating of a polyethylene resin having particles of polytetrafluoroethylene suspended therein for reducing blade pull.